A furniture device, such as a bed or mattress, a seat cushion, or other device, is provided to act on the weight or part of the weight of a being, wherein the device distributes the weight of the body of the being over a part of a surface of the furniture device. Depending on how the device distributes the weight of the being, it will appear as soft or firm. The degree of firmness of such a furniture device is dependent on the properties of the elastic element, such as for example the spring constant or the air pressure. Another parameter that influences the degree of firmness is the arrangement of the elastic element or elements in the furniture device; a pre-tensioned helical spring is harder than a free helical spring, same for an air cushion that is compressed; it is harder than a loose air cushion. Thus the firmness of a furniture device such as a mattress is usually set during manufacturing.
In known furniture devices with properties according to the field of the invention, the firmness of the device is adjustable by deforming the elastic members and thus pre-tensioning them. A mechanism comprising a deformation member, which is capable of deforming the elastic members is used to adjust the firmness of the device or mattress. The firmness of such furniture devices may be adjusted by the being or the user, even after manufacturing of the device. The firmness of the elastic members may also be adjusted when the furniture is used over a period of time allowing compensating for possible changes of its properties.
Contemporary furniture devices with the above described properties often comprise elastic members with a so called pocket spring design, wherein each elastic member comprises a spring element and a flexible envelope that encloses the spring so that the spring is caught in the flexible envelope. Such pocket spring designs allow each spring to deform itself without affecting the adjacent springs. However, the known pocket spring design mattresses cannot be combined with mechanisms that allow the adjustment of the firmness of the spring without loosing the ability to deform itself without affecting the adjacent springs.
WO2005/053466 discloses an upholstered unit such as for example a bed or mattress including a plurality of pocketed springs and at least one inflatable member located above and/or below of at least some of the pocketed springs. WO2005/053466 discloses the use of an inner pocketed spring arranged within an outer pocketed spring, whereby these pocketed springs may be arranged on an inflatable member. The build up of the upholstered unit according to this disclosure is complicated, heavy and due to the many inflatable members proposed also prone to failure.
EP2245967 A1 discloses a furniture device adapted to receive the weight of a being, comprising a section with a fundament, a plate member and a set of elastic members. The elastic members are connected to the fundament via an array of connections, a net member and connection members and they are embedded on the plate member. The plate member is arranged above the fundament with respect to the ground and it can be displaced by a deformation member, thereby pre-tensioning the elastic members. The elastic members comprise an elastic element and a flexible envelope embedding the elastic element. The connection members are attached to the net members and the net member is attached to the array of connections. The net member is a solid grid shaped element. The use of a net member enhances the complexity of manufacturing, build-up and the weight of the furniture device. Further, when the weight of a being acts on the device, it may affect adjacent areas on the same section or neighbouring sections of the device via the net member, since this net member is preferably a solid grid.